Electromagnetic rail guns are well known to those skilled in the art. See, for example, applicant's allowed, copending patent application Ser. No. 07/392,199, the disclosure of which is hereby incorporated by reference into this specification. Also see Japanese patent number 63-251799. One substantial problem with these rail gun systems is that at least about 70 percent of the energy provided to such a system is lost as contact friction.
It is known that nuclear fuel pellets must be moved at a relatively high velocity and low temperature in order to reach the center of the reactor intact. Thus, as is discussed in Japanese patent number 64-23098, in a nuclear fusion reactor, the fuel pellets must travel a long distance before they reach the center of the reactor. Because the temperatures along the travelling path are relatively high, the pellets (which contain hydrogen, deuterium, or tritium in ice phase) may evaporate before they reach the center of the reactor unless their velocities are greater than about 10 kilometers per second.
The injection of frozen pellets composed of the isotopes of hydrogen is widely used for refueling fusion power reactors. See, e.g., a review article by S. L. Milora entitled "Review of Pellet Fueling," Journal of Fusion Energy, Vol. 1, No. 1 (1981).
In a 1989 article by S. L. Milora, "Review of hydrogen pellet injection technology for plasma fueling applications," Journal of Vacuum Science Technology, Volume A7, pages 925-937 (May/June, 1989), the velocity desired for transferring the nuclear fuel pellets again was discussed. The author disclosed that " . . . velocities of 3.8 km/s have already been achieved with two stage light gas guns, and the prospects for attaining 5 km/s in the near future appear to be good."
An article by M. J. Gouge et al., "Design considerations for single-stage and two-stage pneumatic pellet injectors," Review of Scientific Instrumentation, Volume 60, pages 570-575 (April, 1989) also discloses that a velocity of from 4 to 6 kilometers per second might be achieved for such fuel pellets with two-stage pneumatic injectors.
One means of obtaining the required velocity of higher than 10 kilometers per second is proposed by F. Winterberg in an article entitled "Circular Magnetic Macroparticle Accelerator for Impact Fusion," Nuclear Fusion, Volume 30, No. 3, pages 447-451 (1990). Winterberg's proposal involves the use of a gram-size superconducting macroparticle. Winterberg proposes to accelerate such macroparticle to the velocity needed for impact fusion by means of a travelling magnetic wave. One problem with such proposal, when the known high Tc superconductors are embedded in an insulator (as proposed by Winterberger), diffusion often occurs with resulting degradation of the superconductor properties.
The aforementioned Japanese patent number 64-23098 disclosed a device for discharging a fuel pellet. The device of this patent was comprised of pulse coils surrounding superconductive or magnetic rail carrying pellets which were coated with superconducting or magnetic material. However, the device of this patent does not disclose a system which affords stable levitation and projection. There is no disclosure in the Japanese patent of the type of superconductor to be used or of any means for stabilizing the levitating object to be moved. In addition, there is no disclosure in the patent of the means for confining the projectile in a direction transverse to its flying direction.
It is an object of this invention to provide a mass transfer system which is at least about 80 percent efficient.
It is another object of this invention to provide a mass transfer system in which one or more nuclear fuel pellets is moved through a cavity at a speed greater than 10 kilometers per second.
It is yet another object of this invention to provide a mass transfer chamber which is comprised of means for stabilizing a levitated object disposed within the chamber.
It is yet another object of this invention to provide a means for preparing magnetized nuclear fuel pellets.
It is yet another object of this invention to provide a process for preparing a chamber coated with a film of superconductive material.
It is yet another object of this invention provide a process for coating nuclear full pellets with superconductive material.
It is yet another object of this invention to provide a process for preparing a chamber coated with a film of magnetic material.